Method and apparatus for locating an available parking facility

ABSTRACT

In a method and an apparatus for finding an available parking lot, when information about an available parking lot is requested, a locating system first determines the current motor vehicle position, and finds the possible parking lots in a search area on the basis of this position. The data about parking lots are preferably transmitted using the TMC channel of the Radio Data System (RDS). If there are several cities in the search area, then a corresponding selection for a city can be made using an input device. Furthermore, districts with parking lots located in these districts can be selected, in order to find a parking lot as close to the destination as possible. In the case of P+R lots, the connections to the public transit system are also output, along with additional information, for example the train frequency. The apparatus is integrated into a car radio, so that the receiver part, input device, and displays of the car radio can be utilized.

FIELD OF THE INVENTION

The present invention relates to a method and an apparatus for findingan available parking lot or parking garage.

BACKGROUND INFORMATION

Publication "Verkehrsmanagement Stadtpilot"(Traffic Planning CityPilot), Funkschau 3/1994, pages 49 to 51, a "City-Pilot" describes amethod with which a driver can already obtain all the importantinformation relating to available parking lots as well as all lines ofthe public transit system, with departure times and connections, for amajor city and its commuter area. The required data for this city areeither transmitted directly to the terminal, via the radio data system(RDS system), or also via variable message signs which are controlledvia RDS. The City-Pilot has a display on which the desired data can bedisplayed by pressing keys the appropriate number of times. However, itis disadvantageous that the device cannot determine its own location.Therefore all the received data have to be manually searched until acertain destination with an available parking lot is found. In view ofthe large number of data which can be transmitted with the RDS system,this search process can be very time-consuming. Using this process whilein a moving motor vehicle, for example, could therefore overly distractthe driver from the traffic events around him.

SUMMARY OF THE INVENTION

In contrast, the method of procedure, according to the present inventionfor finding an available parking lot for a motor vehicle has anadvantage that by determining the current position of the motor vehicle,a preselection of the data can take place, and only the data which liewithin the given search area are displayed. The search area can beselected in such a way that only one city or one district is covered,and the available parking lots or parking garages for this city ordistrict are output. If, on the other hand, there are several cities ordistricts in the search area, the driver can make a simple selection bypressing the appropriate keys. With the apparatus according to thepresent invention, the RDS system of a car radio can be used todetermine an available parking lot, so that the advantages of the carradio, namely the receiver part, the existing display and any inputkeys, as well as a control of a microprocessor, for example, can also beused. This results in significant cost advantages in the production ofthe apparatus according to the present invention.

It is further advantageous that a simple and current selection of adestination can be made by assigning the keys to the districts.

Since the parking lots or parking garages are assigned to a district,the parking lot can therefore be displayed automatically, withoutfurther selection measures being required.

Another advantage according to the present invention is that the linesof the public transit system and/or their schedules are also output inthe selected district. Since the selected district is relatively small,its representation is easily surveyed, particularly if an electronicstreet map is being used.

It is particularly advantageous that in the apparatus for carrying outthe method for finding an available parking lot, the selection of adistrict can be made using an input device which is structured as a keypad. Pads with nine, ten or sixteen keys are usual, for example, forcalculators, and rocker keys are usual for car radios, all of which arefamiliar to the user. It is particularly advantageous if each key of akey pad is assigned to at least one district, in accordance with itsgeographical location. This simplifies operation when selecting adistrict, so that the driver can easily operate the device even whiledriving.

A particularly precise and targeted selection of the destination, i.e.of a district, is achieved by repeatedly pressing a key. By assigningthe keys multiple functions, space is saved on the front panel of thecar radio, without losing clarity for the selection of a district.

By using a navigation or destination guidance system, there is theadvantage that the driver is automatically guided to the availableparking lot or parking garage. This is particularly advantageous forpersons who are not from that city.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a first exemplary embodiment of a car radio according tothe present invention.

FIG. 2 shows a block schematic of a device according to the presentinvention.

FIG. 3a shows a first example of a search area, i.e. a commuter area.

FIG. 3b shows a second example of the search area.

FIG. 4 shows a first example of parts of a street map.

FIG. 5 shows a second example of parts of the street map.

FIG. 6a shows districts within the street map.

FIG. 6b shows a first example district allocation as illustrated in FIG.6a to keys of a key pad according to the present invention.

FIG. 6c shows a second example district allocation as illustrated inFIG. 6a to keys of the key pad according to the present invention.

FIG. 7a shows other possible districts within the street map.

FIG. 7b shows a first example district allocation as illustrated in FIG.7a to keys of a key pad according to the present invention.

FIG. 7c shows a second example district allocation as illustrated inFIG. 7a to keys of the key pad according to the present invention.

FIG. 8 shows a flow chart of the method according to the presentinvention.

FIG. 9 shows an example of a status table.

FIG. 10 shows an allocation table for parking facilities.

FIG. 11 shows a first sequence of a data telegram.

FIG. 12 shows a second sequence of the data telegram.

FIG. 13 shows a third sequence of the data telegram.

FIG. 14 shows a fourth sequence of the data telegram.

FIG. 15 shows a selection table.

DETAILED DESCRIPTION OF THE INVENTION

An exemplary embodiment according to the present invention illustratedin FIG. 1 shows a car radio 11, which has a key pad 12 on the left side.The key pad 12 is shown to be similar to a touch-tone telephone, withtwelve keys, where the keys 0 to 9 are used to select districts. Key Pserves to activate the parking lot search, and a key * serves to stopthe current function or to switch to the radio function. Another key 14serves as a selection key, preferably a rocker key, in order to select adestination or a district on a display 13, if this is necessary. Forreasons of clarity, the operating elements for the car radio or itscassette player are not shown in FIG. 1. The display 13 can be used bothfor displays of the car radio function, and for the parking lot search.

FIG. 2 shows a block schematic of the car radio 11. In addition to aconventional receiver part 21 with an antenna 20, the car radio isequipped with the Radio Data System or decoder (RDS) 22. The RDS system22 has a Traffic Message Channel (TMC), which is designed fortransmission of traffic messages for one or more district segments. TheRDS decoder 22 is connected with a message memory in which the currenttraffic messages are stored and can be called up if needed. The RDS-TMCsystem and decoder are known as such to one of ordinary skill in the artand therefore do not require any further explanation. Data concerningstationary traffic, variations i.e. available parking lots, parkinggarages or P+R lots, can now be transmitted via free blocks of the TMCchannel. The car radio 11 is furthermore connected with a locatingsystem 24, which can determine the current vehicle location using wheelsensors, a compass or the Global Position System (GPS). The locatingsystem 24 can also be connected with a navigation and destinationguidance system 24a. A microprocessor is provided as a controller 23,which is connected with the connected systems as well as the inputdevice 12 and a data output device 13. Furthermore, the controller 23 isconnected with a memory 25, which contains a table for the towns andtheir coordinates. Also, additional data such as a commuter area 15 ofthe towns, (see, e.g., FIG. 36) coordinates and names of parkinggarages, and their allocation to districts S, can be stored in memory inthe table. FIGS. 3a, b schematically show the sequence of a searchprocess for a parking lot or a parking garage. When approaching a city Aor B, when the key P (see, e.g., FIG. 1) is activated, this isrecognized as being a request for a search of parking possibilities,preferably in a parking garage. Alternatively, by pressing another keyor pressing the key P several times, a selection can be preselected forP+R parking lots (Park and ride). FIGS. 3a and 3b show a vehicle Fcovering a search area 10 which includes the cities A and B, in thedirection of travel. The search area 10 can lie in a circle in front ofthe vehicle F, for example. If the desire to find a parking possibilityis expressed by pressing the key P, the controller 23 first gets thecurrent vehicle position from the locating system 24. On the basis ofthis position and the coordinates from commuter area (Table) 15, thecities A and B which lie in the search area 10 are selected. The citiesA, B are now output on the data display 13, using a visual display orover a loudspeaker. The driver can then select whether he is looking fora parking lot in city A or B, by pressing the selection key 14. In FIG.3b, on the other hand, it is assumed that instead of the search area 10,each city A and B has its own commuter area 15. If, for example, thevehicle F is in the commuter area 15 of the city A, then the RDS datafor city A are directly selected. This information about the availableparking lots, parking garages or P+R lots was previously transmitted tothe memory of the RDS/TMC channel in the reception area in question, forall the cities. As shown in FIGS. 4 and 5, a further selection is madeusing the key pad 12. In FIG. 4, a nine-key pad is provided, divided upinto a 3×3 matrix. The individual keys 1 to 9 are now geographicallyassigned to the city area, for example, to city A, in such a way thatthe upper row of keys, 1 to 3, corresponds to the northern parts of thecity, the center row of keys, 4 to 6, corresponds to the center parts ofthe city, and the bottom row of keys, 7 to 9, corresponds to thesouthern parts of the city. By pressing the key 3, for example, thenortheastern part of city A is selected. There is a parking garage P2 inthis district, and it is now automatically output as a destination.

FIG. 5 shows an alternative key arrangement for searching for a P+R lotwith a key pad 12, where this key pad has only five keys. The key 3covers the central district, while the keys 1, 2, 4, 5 cover theoutlying districts. If the northeast part of city A is selected bypressing the key 2, then the controller 23 finds a P+R lot in thisdistrict. The P+R lot is assigned to this district S, since it can bereached via a connection of the public transit system. The same holdstrue for parking lots or parking garages. In this case, the connectionof a public transit system, for example line 5, is drawn in; this lineleads directly to the northeastern part of the city A. As additionalinformation, the driver receives the departure frequency, for exampleevery five minutes, and/or the schedules, so that he is also informedabout train frequency. For a selection, the districts S must be assignedto the keys of a key pad.

FIGS. 6a through 6c show the allocation of downtown districts 0 to 15 toa 9-key pad. FIG. 6b shows an abstract allocation, like a grid, of thedistricts S. These grid areas can then be assigned to a key pad. Theoutlying districts are ignored in this connection, since they are notrelevant in the present example. If a 9-key pad shown in FIG. 6c isused, then the keys 1 to 9 can be assigned to the districts 0 to 15indicated, by using the following allocation table:

    ______________________________________                                        Allocation Table 1                                                            Keys                                                                          1         2      3      4    5    6    7   8    9                             ______________________________________                                        Districts                                                                            0      1      2    4    5     7    9  13   14                                 1      2      3    8    6    11   12  14   15                                 4             7         9         13       14                                                         10                                             ______________________________________                                    

Analogous to FIGS. 6a, 6b, and FIGS. 7a, 7b show another exemplaryembodiment, according to the present invention in which the outlyingparts of the districts 0 to 15 (FIG. 7a) are assigned to the grid areas0 to 15. FIG. 7c shows an input device 12 with a 9-key pad, which isassigned to the following allocation table 2, for example. It isadvantageous if switching from the downtown area to the outlying area ofthe city is done by pressing the corresponding keys twice. In order toaccess the outlying district 1, for example, the key 1 is pressed twice,while pressing it once selects the district 1 according to FIG. 6a.

    ______________________________________                                        Allocation Table 2                                                            Keys (press 2x)                                                               1        2      3     4    5      6    7    8   9                             ______________________________________                                        Districts                                                                            0     1      3   6    downtown                                                                              7   10   13  11                                 4     2      5   8    district                                                                             10   12   14  15                          ______________________________________                                    

FIG. 8 illustrates the functioning of the method and apparatus accordingto the present invention, for finding an available parking lot, ingreater detail. To activate the search system, the key P of the key pad12 is pressed in position 80. In position 81, the locating system 24,for example the navigation system "Travel Pilot," or using the GlobalPosition System, determines the current vehicle position and passes iton to the controller 23. Locating systems are commercially available andtherefore do not require any further explanation. In position 82, thecurrent travel direction is determined from the old position and thecurrent position. In the travel direction, a search area is now formedas shown in FIG. 3a, which can have a diameter of 20 km, 30 km or 50 km,for example, taking the current vehicle position into account. Insteadof the search area 10, a commuter area 15 assigned to a city A can alsobe used. The coordinates of the city as well as the size of the commuterarea can be stored in memory in a selection table (See e.g., FIG. 15).The RDS/TMC messages occur in sequences, where each sequence is dividedinto several blocks. For P+R information, FIG. 14 shows a firstsequence, in which the various town codes of the various cities aretransmitted in block 4. As is further evident from FIG. 4, a grid areanumber for the district identification, as well as the means of publictransit, such as intracity trains, streetcars, subway trains, busses orintercity trains are indicated or transmitted in block 3. FIG. 11 showsa similar sequence, but this one contains information about thestationary traffic, i.e. concerning parking spaces in parking garages,without a connection to the public transit system. The town codeindicates the town for which the messages concerning stationary trafficvariations apply. In the memory 25, additional town coordinates arestored for the town codes. For example, as shown in FIG. 15, these towncoordinates are 34/43 for Hildesheim, 50/81 for Hanover, and 70/90 forSalzgitter. In position 83, the coordinates of the current vehicleposition are now compared with the coordinates in the search area 10,i.e. commuter area 15. In position 84, an inquiry is made whether thesearch area is smaller than the difference between the current vehicleposition and the coordinates of the city (FIG. 15). If the search area10 is smaller, i.e. if no city was found, then the search area isexpanded by a predetermined value, for example to 30 km or 50 km. If nocity was found, then the search process is broken off in position 85,and the program is started again with position 80. If, on the otherhand, one or more cities are found in the search area, then these citiesare displayed in position 86. If several cities were found, then amanual-selection of the cities displayed can be made in position 87,using the selection key 14. In position 88, the selected city isconfirmed, for example by pressing the key P. In position 89, the keypad 12 can now be used to select a desired destination area, i.e. one ormore districts S corresponding to FIGS. 6a, 7a and the allocation tables1, 2, by pressing one of the keys. By means of selecting the district S,the messages from the RDS memory which are stored for this district arenow selected in position 90. In particular, these are messagesconcerning available parking lots, parking garages or P+R lots.

The size of a city determines the number of required districts S, i.e.the required grid areas. For small cities, for example, the 16 gridareas (FIG. 6a) are sufficient. For larger cities, more grid areas areneeded, in order not to reduce the accuracy. The most detailed gridpossible is always a goal, if only in order to make a logical allocationof the grid areas to the most varied types of input devices possible.Another restriction of the grid areas results from the available databits in the TMC channel. For the TMC channel, protocols have alreadybeen established for the transmission of data structures. Such aprotocol is known under the name ALERT C. If the structures are takeninto consideration, then four bits are available for the grid areanumbering, so that a total of 16 different grid areas is obtained. Inaddition, the event is transmitted for the 16 grid areas. An event forparking garages, for example, is the "information for stationary trafficin the downtown area" of a city. Corresponding to FIG. 6a, theindividual districts and grid areas are numbered consecutively. Eachparking lot is assigned to a grid area in accordance with itsgeographical location in the district, or on the basis of itscity-planning allocation. Using the eleven bits which are available forevents, more events than are currently being utilized can be defined, sothat additional events can also be defined. Cities which cannot make dowith the basic grid can produce a ring-shaped expanded network inaccordance with FIG. 7a, by using additional defined events, and displaythe districts on it. For example, the events can be as follows:

2000 "Info for the stationary traffic in the downtown area"

2001 "Info for the stationary traffic in outlying area 1"

2002 "Info for the stationary traffic in outlying area 2"

2003 . . . etc.

The district identification (event+grid area) is transmitted in everymessage, in block 3 of the first sequence (FIG. 14, 11).

In the vehicle device, preferably the car radio 11, one or moredistricts S are assigned to a key, depending on the type of input device(see, e.g., FIGS. 6c, 7c, allocation tables 1, 2).

A following example will be explained below in greater detail:

A selection of a parking garage is made, for example, according to thetable in FIG. 10. For example, according to the left column, all theparking garages P1, P2, P3 and P4 which are assigned to the selecteddistrict S are displayed. If, for example, the key 1 was pressed inaccordance with the FIGS. 6a and 6c, then the districts 0, 1, 4 areselected, taking into consideration the allocation table 1. As shown inFIG. 10, in these districts 0, 1, 4, the parking garages P1, P2 areassigned to the district 0 (right column), the parking garage P3 isassigned to the district 1, and the parking garage P4 is assigned to thedistrict 4. If a parking garage in the district 0 is desired, then theparking garage P1 or P2 can be selected. At the same time, thecoordinates of this parking garage are displayed, so that the way to theparking garage can also be displayed on a street map, or the destinationroute can be output acoustically, for example in connection with anavigation system. FIG. 9 now shows a table with the occupancy status ofthe available parking garages. The occupancy status is transmitted withthe second sequence of the TMC protocol (FIG. 12), and indicates, forexample in a text message, whether only individual parking spaces arestill available (Code 00), whether there is plenty of space (Code 01),whether the parking garage is full (Code 02), or no information is given(Code 03).

For finding a P+R lot, a similar allocation as for the parking garagesis selected. The event numbers and the related events differ by theadditional information about the public transit system, and can be asfollows, for example:

2005 "Bus connection at P+R in downtown area"

2005 "Bus connection at P+R in outlying area 1"

2006 "Bus connection at P+R in outlying area 2"

2008 . . . etc.

In addition, in a second sequence for a district, the P+R lots whichhave one or more public transit connections with the selected district Sare transmitted. Each data set about a P+R lot consists of two fields (aand b field). In the a field, the travel time from the P+R lot to theselected district is indicated. In the b field, the train frequency inminutes is indicated. For the P+R lots, the controller 23 looks for themessages which relate to the selected district S. Therefore the closestP+R lot can automatically be selected, since the position of both theselected district and the P+R lot are known. If there is a choice ofmore than one P+R lot, then a certain lot can be selectively searchedfor. Finally, in position 91 (FIG. 8), the occupancy status of theselected parking garage is also indicated (FIG. 9). Of course theinformation can be displayed summarized in a table, so that greaterclarity is possible.

What is claimed is:
 1. A method for locating at least one availableparking facility for a motor vehicle, comprising the steps of:requestingparking data corresponding to the at least one available parkingfacility; determining a current position of the motor vehicle using alocating system when the parking data is requested; receiving theparking data related to the at least one available parking facilitycorresponding to at least one assigned town code; predetermining asearch area corresponding to the current vehicle position; selecting theat least one assigned town code of at least one town positioned in thesearch area; at least one of optically outputting and acousticallyoutputting at least one town name corresponding to the at least oneselected town code; selectively choosing at least one of a destinationarea and a district from the at least one town name using an inputdevice, the destination area being divided into predetermined districts,the input device including a key arrangement, each of the districtsbeing assigned to a key of the key arrangement, the key arrangementbeing associated with a geographical location of the districts;selecting at least one message associated with the at least oneavailable parking facility for the selected district; and outputting atleast one of the at least one available parking facility correspondingto the at least one message.
 2. The method according to claim 1, whereinthe step of receiving the parking data is performed using a Radio DataSystem.
 3. The method according to claim 2, further comprising the stepof:receiving RDS data from the Radio Data System, wherein the at leastone message is selected from the RDS data.
 4. The method according toclaim 1, wherein the at least one available parking facility correspondsto the selected district, and further comprising the stepof:automatically displaying the at least one available parking facilitycorresponding to the selected district.
 5. The method according to claim1, further comprising the step of:assigning pathways of a public transitsystem to the selected district for outputting the pathways.
 6. Themethod according to claim 5, wherein the pathways of the public transitsystem include schedules.
 7. The method according to claim 5, furthercomprising the step of:outputting the pathways of the public transitsystem and the at least one available parking facility on an electronicstreet map.
 8. The method according to claim 1, wherein each of the atleast one town has a corresponding assigned commuter area, and furthercomprising the step of:selecting at least one available parking facilityassigned to one of the at least one town if the current vehicle positionis substantially in the commuter area.
 9. An apparatus for locating atleast one available parking facility for a motor vehicle, comprising:aRadio Data System (RDS) transmitting RDS data and including an RDSreceiver; a message memory for storing at least one assigned town codecorresponding to at least one town and for storing messagescorresponding to the at least one available parking facility; an inputdevice including input keys and selecting at least one of a destinationarea and at least one district from the at least one assigned town code,the input keys of the input device being arranged as one of a key padand a rocker key and being assigned to predetermined districts, theinput keys including top keys, bottom keys and at least one further key;a data output device receiving at least one assigned town code andoutputting at least one town name corresponding to the at least oneassigned town code; a locating system determining a current position ofthe motor vehicle; and a controller connected to the locating system andselecting the at least one assigned town code corresponding to assigneddata of the at least one available parking facility in the destinationarea using the RDS data, wherein the top keys correspond to northerndistricts of the predetermined districts, and the bottom keys correspondto southern districts of the predetermined districts, and wherein the atleast one further key selects the destination area and requests a searchfor locating the at least one available parking facility.
 10. Theapparatus according to claim 9, wherein the Radio Data System includes aTraffic Message Channel (TMC) having a data protocol for selectivelytransmitting the assigned data of the at least one available parkingfacilities.
 11. The apparatus according to claim 9, wherein the key padincludes at least one of a 9-key pad, a 10-key pad and a 16-key pad. 12.The apparatus according to claims 9, wherein the districts have a highresolution output obtained by one of repeatedly pressing one of theinput keys of the input device and pressing one of the input keys atvarious times.
 13. The apparatus according claim 9, wherein theapparatus is connected to one of a navigation guidance system and adestination guidance system for indicating a travel route to the atleast one available parking facility having a location closest to adesired destination.